Install Hour Meter on Indoor Unit

[tickjob]

Hi,

I have a multi-split system, for example 1 outdoor unit and 3 indoor units. I rented out 2 room with aircon. Hence, I need to charge each room usage of the aircon. One way I am thinking of is to install hour meter ( http://www.kep.com/catalog/ii/pages/timers.html ). Can someone advise where/how can I install this hour meter on the indoor unit?

[JoeAT50A]

How will you apportion for all the 3 indoor units which are shared from a same outdoor unit?
Option1>> take the total kWhr from outdoor unit then apportion based on usage hours or capacity or just equally or floor areas. (in fact not fair for two tenants especially who normally used to set 25 to 27C).
Option2>> Just simply divided by 3 (if capacities are same).

[tickjob]

I want to install the hour meter on each indoor unit. I will charge each room tenant by number of hour usage, for example, $0.50 per hour. So now my problem is how to install hour meter on indoor unit, which points can I connect my hour meter?

[JoeAT50A]

Yup, No point to install at indoor units, you can't get any useful information from there. Meter count only indoor fan motor power input (kW) and runtime (hr). Up to 95% of consumption come from outdoor unit.
Based on indoor is the wrong calculation after all.
For example with 9000 btu/hr indoor unit
Indoor fan motor input = 15Watt =0.015kW whole day run (24Hr)
So will you charge this 0.015x24x30(days)x0.5$=5.40$ per month

But if you insist to install, buy simple clamp meters. Single phase are cheaper and simple.
Just clamp on the Live wire.

[tickjob]

I just want to charge based on hour usage, flat rate, $0.50 per hour, not just the electricity consumption but also all the capital cost and maintenance cost.

Whicht hour meter come with "clamp" to the measure the live wire current?

[tickjob]

clamp watt hour meter also can be used, I just need to multiply by a number to get $0.50 per hour. Any one know about this product available?

[JoeAT50A]

http://www.efergy.com/index.php/default/local-distributor
or
http://www.efergy.com/

Electrique Energie & Metering PL
+65 6741 8951
6741 9325
www.electrique.com.sg

[tickjob]

I just went to sungei road and found a single phase KWH meter KM-EKWH-1011, it has the size of MLCB, see the picture. I asked the shop how to connect and they don't know. Could some of you adivse. See the picture attached.

[tickjob]

try to attach picture........................82828283

[Brian_UK]

If the shop doesn't kow and you don't either I would suggest that you employ an electrician.

[tickjob]

I have tried and tested it with real load, it works!
see attached picture.8286

[tickjob]

After some search, found many other made/brand. The Key word is "DIN Rail", in full "single phase DIN Rail KWH mter".

[tickjob]

or "Single Phase DIN Rail Electricity Meter".

[tickjob]

I bought S$65 from a shop in Singapore.
ebay selling about S$45: http://www.ebay.com.sg/itm/50-KW-HOUR-METER-ELECTRIC-ELECTRICITY-KWH-SUPPLY-DIN-RAIL-DIGITAL-SINGLE-PHASE-/280756954023?pt=UK_AudioElectronicsVideo_Video_TelevisionSetTopBoxes&hash=item415e6b23a7#shId

[tickjob]

This china made one even cheaper: http://www.ebay.com.sg/itm/LCD-5-32A-230VAC-DIN-Rail-Kilowatt-Hour-kwh-Meter-/120770659530?pt=LH_DefaultDomain_0&hash=item1c1e7e04ca